N-halogenalkyl-c.c-dialkylbarbituric acids and preparation of the same.



UNITED STATES PATENT OFFICE.

OTTO WOLFES, F DARMSIADT, GERMANY.

N-I-IALOGENALKYL-C.C-DIALKYLBARBITURIC ACIDS AND PREPARATION OF THESAME.

filed May 28, 1913.

ments in N-Halogenalkyl-C.C-Dialkylbarbi-' turic Acids and Preparationof the Same,

of which the following is a specification.

My invention relates to a method for the preparation ofN-halogenalkyl-O.C-dialkylarbituric acids of the general type:

(Xzhalogenalkyl, Y=hydrogen or halogenalkyl) and consists in treatinghalogenthe residue is dissolved in ether, and the reaction product isfreed from acids by shaking with a solution of sodium bicarbonate. Tocompletely purify it, it is removed from the ethereal solution by icecold dilute s0- lution of caustic potash, purified by animal charcoal,and again' precipitated by slight acidification. The precipitate is thenrecrystallized from 70% alcohol. The product thus obtained proves to bein every respect identical with mono-N-dibromopropyl-(LO-d-iethylbarbituric acid. The .normal course of the condensation ofdibromopropyl urea with diethylmalonyl chlorid is somewhat surprising inView of the fact that Rundquist, in the paper alluded to above, drawsspecial attention to the ready decomposition .of dibromopropyl urea byacids.

Specification of Letters Patent No Drawing. Original application filedDecember 13, 1912, Serial No. 736,628.

Serial No. 770,502.

Patented Sept. 23, 1913.

2. To a solution of 14: parts of sinapolin (sym. diallyl'urea) in 40parts of benzol are added gradually, with stirring, 32 parts of bromindiluted with 40 parts of benzol, taking care to keep the mixture cool.The

benzol is carefully removed by distillation in a vacuum. The residue isthen heated with 20 parts of diethylmalonyl chlorid for 23 hours in avacuum at 120 to 130 C. The reaction produced is dissovled in 100 partsof warm absolute alcohol, purified by the addition of animal charcoal,and cooled on ice; the alcohol is poured off and the viscid oil isboiled with petroleum other (about 40 C.). The residue, insoluble inpetrolether, is crystallized from alcohol. The product obtained,NN-tetrabromodipropyl-0.0-diethylbarbitm'ic acid, forms small.eolorlcssprisms, melting at about ti t" C. On analysis it was found tocontain 54.7% of bromin, whereas for C H ,O,N,Br a content of 54.87;, ofbromin was calculated.

What I claim and desire to secure by Letters Patent is:

l. The method of producin N-halogenalkyl-C.O-dinlkylbarbituric acidswhich consists in treating derivatives of halogenalkyl urea withdinlkylmalonyl-halogenids.

2. The method of producingmono-N-halogenalkyl-(lC-dialkylbarbituricacids which consists in treating derivatives of nmno-N- halogenalkylurea with dialkyln'ialonylhalogenids.

3. The method of producing i'nonoN- bromoalkyl 0.0 diallcylbarbituricacids which consists in treating bromoderivatives of monoalkyl urea withdialkylmalonylhalogenids.

4-. The method -of producing inono-N dihromoalkyl (LC dialkylbarbituricacids which consists in treating dibrom'oderivm tives of monoalkyl ureawith dialkylmalonyl-chlorids.

5. The method of producing mono-N- dibromopropyl-0.0-diethylbarbituricacid which consists in treating dibroinopropyl urea withdiethylmalonylchl orid.

In testimony whereof I atfix my'signature in presence of two witnesses.

OTTO WOLFES.

WVitnesses JEAN GRUND, CARL GRUND.

Divided and this application

